Changes in temperature in a house or building tend to be required at specific periods of the day. For example, in a cold environment, the temperature setting is lower for the night and higher at wake-up time. This produces an instant high electrical power demand coming from a multitude of houses around the same time, which results in problems for electricity supply companies.
Known in the art, there is the U.S. Pat. No. 4,228,511 of SIMCOE et al., describing a system and a method for limiting power demand and for temperature control. According to this invention, a room thermostatic control provides for automatic power defer, i.e. modification of load consumption of electrically energized heating and cooling systems during intervals when there is a peak load demand on the electrical supply system. During power defer ambient indoor temperature is controlled by set point adjustment to minimize discomfort, e.g. by pre-boosting, by ramped temperature deferral at controlled rates, and thereafter by ramped recovery at controlled rates to the reference, i.e. desired, temperature. A circuit sensing external conditions, e.g. outdoor temperature, indicative of power defer, is utilized to generate a power defer signal for enabling modification of the set point. Digital signals are stored for each of a plurality of consecutive real time intervals for heating and cooling modes. A real time clock is utilized to access the digital signals for the current time interval. During presence of a power defer signal set point variation is controlled in accordance to the relevant digital signals for each current time interval.
The following patents also describe different systems or methods for power demand control or temperature control: U.S. Pat. Nos. 4,100,428; 4,167,965; 4,228,511; 4,509,585; 4,909,041; 5,095,715; 5,285,963; 5,361,982; 5,501,268; 5,467,812; 5,678,626 and 5,682,949.
A drawback with the systems or methods of the prior art is that although some of them allow a deferring of the power demand when a peak load occurs, none of them is concerned with a method or a system for spreading over a time period and reducing in intensity the amount of power supplied to a conditioning device when a new setting signal is issued.
An object of the present invention is to provide a method and an apparatus for spreading over a time period and reducing in intensity the amount of power supplied to a conditioning device when a new setting signal is issued.
Another object of the present invention is to perform the above-mentioned spreading over a time period and reducing in intensity in a way where the discomfort for the user is controlled and limited.